VEGA Phoenix PSI Data Fax Modem - Manual (Page 91)

AT Commands
692302 6-3
6 AT Commands
Your modem stores its operating characteristics in a non-volatile memory
(EEPROM). These characteristics can be overwritten using commands and can
thus modify the method of operation of the device. The modem executes
commands as long as it is in command mode. Your modem is automatically in
command mode until you dial a number and establish a connection. You can enter
commands for your modem using appropriate communication software
(e.g., HyperTerminal). The device supports data transmission speeds of 300, 1200,
2400, 4800, 9600, 19,200, 38,400, 57,600, and 115,200 bps.
Modes
The modem can be operated in two modes:
– Command mode: The modem can be configured and controlled via AT
commands. As soon as a connection is established, the modem automatically
switches to data mode.
– Data mode: In this mode, the modem transmits data to the partner.
Command Structure
All commands transmitted to the modem must start with AT and must be confirmed
by pressing ENTER. The commands can be entered in either upper or lower case,
but not a mixture of the two. Spaces may be inserted between the commands so
that the command lines are easier to read.
Correcting a Typing Error
If you make a mistake when entering a command, you can correct it using the
backspace key. Pressing the backspace key deletes the last character entered. The
AT at the start of the command line is not deleted.
Make sure that the baud rate setting for your COM port in your communication
software corresponds to one of these speeds.
AT deletes the last command line executed by your modem (if present) and
prepares your modem for the new command line. In addition, AT informs your
modem of the transmission speed, parity, and character length.
For commands that must be specified by a parameter, a missing parameter
corresponds to parameter 0, e.g., ATM = ATM0.